In-situ structural health monitoring, diagnostics and prognostics system utilizing thin piezoelectric sensors

Abstract

A method of detecting a damaged feature within a structure includes embedding a plurality of thin piezoelectric ceramic sensors on the structure. A first sensor is excited so that the first sensor produces a responsive signal in the structure. The responsive signal is received at a second sensor. The presence or absence in the received responsive signal of at least one predetermined signal characteristic is determined, where the predetermined signal characteristic is related to existence of the damage feature.

Description

[0001]This application claims the benefit of U.S. Provisional Application No. 60 / 267,650, filed Feb. 8, 2001 and entitled “In-situ Structural Health Monitoring, Diagnostics and Prognostics System Utilizing Smart Active Sensors with Embedded Intelligence and Wireless Installation,” the entire disclosure of which is incorporated by reference herein.BACKGROUND OF THE INVENTION[0002]It has been recognized that there is a need to monitor the existence and effects of damage and corrosion in structural materials. Aircraft components provide a much publicized example, but the need exists in a variety of other structures, for example pipelines and building members. To detect defects, traditional modal analysis testing generally relies on structural excitation and vibration pickups. Structural excitation methods, in turn, usually employ either harmonic sweep or impulse excitation. The former method is more precise and can focus on resonant frequencies, while the latter is more expedient. Vibr...

AI Technical Summary

Problems solved by technology

Ultrasonic sensors, which are relatively bulky and expensive, are typically used in portable devices placed in communication with the structure of interest so that the crystals propagate ultrasonic waves into the material.

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